diff --git a/src/Nazara/Core/ConditionVariable.cpp b/src/Nazara/Core/ConditionVariable.cpp
index ac8dcd50a..b9194d233 100644
--- a/src/Nazara/Core/ConditionVariable.cpp
+++ b/src/Nazara/Core/ConditionVariable.cpp
@@ -11,7 +11,7 @@
 #elif defined(NAZARA_PLATFORM_POSIX)
 	#include <Nazara/Core/Posix/ConditionVariableImpl.hpp>
 #else
-	#error Thread condition has no implementation
+	#error Condition variable has no implementation
 #endif
 
 #include <Nazara/Core/Debug.hpp>
diff --git a/src/Nazara/Core/File.cpp b/src/Nazara/Core/File.cpp
index 6c38f30f7..d0959b56e 100644
--- a/src/Nazara/Core/File.cpp
+++ b/src/Nazara/Core/File.cpp
@@ -85,10 +85,10 @@ void NzFile::Close()
 
 bool NzFile::Delete()
 {
-	NazaraLock(m_mutex)
-
 	Close();
 
+	NazaraLock(m_mutex)
+
 	return Delete(m_filePath);
 }
 
@@ -266,11 +266,12 @@ std::size_t NzFile::Read(void* buffer, std::size_t typeSize, unsigned int count)
 
 bool NzFile::Rename(const NzString& newFilePath)
 {
-	NazaraLock(m_mutex)
-
 	bool opened = IsOpen();
+
 	Close();
 
+	NazaraLock(m_mutex)
+
 	bool success = Rename(m_filePath, newFilePath);
 	if (success)
 		m_filePath = NormalizePath(newFilePath);
@@ -283,10 +284,10 @@ bool NzFile::Rename(const NzString& newFilePath)
 
 bool NzFile::Open(unsigned long openMode)
 {
-	NazaraLock(m_mutex)
-
 	Close();
 
+	NazaraLock(m_mutex)
+
 	if (m_filePath.IsEmpty())
 		return false;
 
@@ -314,8 +315,6 @@ bool NzFile::Open(unsigned long openMode)
 
 bool NzFile::Open(const NzString& filePath, unsigned long openMode)
 {
-	NazaraLock(m_mutex)
-
 	Close();
 
 	SetFile(filePath);
@@ -361,10 +360,10 @@ void NzFile::SetEndianness(nzEndianness endianness)
 
 bool NzFile::SetFile(const NzString& filePath)
 {
-	NazaraLock(m_mutex)
-
 	if (IsOpen())
 	{
+		NazaraLock(m_mutex)
+
 		if (filePath.IsEmpty())
 			return false;
 
@@ -446,8 +445,6 @@ bool NzFile::Write(const NzString& string)
 
 std::size_t NzFile::Write(const void* buffer, std::size_t typeSize, unsigned int count)
 {
-	NazaraLock(m_mutex)
-
 	#if NAZARA_CORE_SAFE
 	if (!IsOpen())
 	{
@@ -462,6 +459,8 @@ std::size_t NzFile::Write(const void* buffer, std::size_t typeSize, unsigned int
 	}
 	#endif
 
+	NazaraLock(m_mutex)
+
 	if (!buffer || count == 0 || typeSize == 0)
 		return 0;
 
diff --git a/src/Nazara/Core/MemoryManager.cpp b/src/Nazara/Core/MemoryManager.cpp
index a91133234..739c75d82 100644
--- a/src/Nazara/Core/MemoryManager.cpp
+++ b/src/Nazara/Core/MemoryManager.cpp
@@ -209,6 +209,7 @@ void NzMemoryManager::Initialize()
 
 	#ifdef NAZARA_PLATFORM_WINDOWS
 	InitializeCriticalSection(&s_mutex);
+	//#elif defined(NAZARA_PLATFORM_POSIX) is already done in the namespace
 	#endif
 
 	s_initialized = true;
@@ -224,6 +225,8 @@ void NzMemoryManager::Uninitialize()
 {
 	#ifdef NAZARA_PLATFORM_WINDOWS
 	DeleteCriticalSection(&s_mutex);
+	#elif defined(NAZARA_PLATFORM_POSIX)
+	pthread_mutex_destroy(&s_mutex);
 	#endif
 
 	FILE* log = std::fopen(s_MLTFileName, "a");
diff --git a/src/Nazara/Core/Posix/ConditionVariableImpl.cpp b/src/Nazara/Core/Posix/ConditionVariableImpl.cpp
index d75af776e..7a8ba8fc3 100644
--- a/src/Nazara/Core/Posix/ConditionVariableImpl.cpp
+++ b/src/Nazara/Core/Posix/ConditionVariableImpl.cpp
@@ -35,7 +35,7 @@ bool NzConditionVariableImpl::Wait(NzMutexImpl* mutex, nzUInt32 timeout)
 {
 	// get the current time
 	timeval tv;
-	gettimeofday(&tv, NULL);
+	gettimeofday(&tv, nullptr);
 
 	// construct the time limit (current time + time to wait)
 	timespec ti;
diff --git a/src/Nazara/Core/Posix/DirectoryImpl.cpp b/src/Nazara/Core/Posix/DirectoryImpl.cpp
index 50451edbe..9bd78e65f 100644
--- a/src/Nazara/Core/Posix/DirectoryImpl.cpp
+++ b/src/Nazara/Core/Posix/DirectoryImpl.cpp
@@ -82,14 +82,15 @@ bool NzDirectoryImpl::Exists(const NzString& dirPath)
 NzString NzDirectoryImpl::GetCurrent()
 {
 	NzString currentPath;
-	char* path = new char[_PC_PATH_MAX];
+	char* path = getcwd(nullptr, 0);
 
-	if (getcwd(path, _PC_PATH_MAX))
+	if (path)
+	{
 		currentPath = path;
+		free(path);
+	}
 	else
-		NazaraError("Unable to get current directory: " + NzError::GetLastSystemError());
-
-	delete[] path;
+		NazaraError("Unable to get current directory: " + NzError::GetLastSystemError()); // Bug: initialisation -> if no path for log !
 
 	return currentPath;
 }
diff --git a/src/Nazara/Core/Posix/MutexImpl.cpp b/src/Nazara/Core/Posix/MutexImpl.cpp
index dee6078dc..0ed78092f 100644
--- a/src/Nazara/Core/Posix/MutexImpl.cpp
+++ b/src/Nazara/Core/Posix/MutexImpl.cpp
@@ -7,7 +7,7 @@
 
 NzMutexImpl::NzMutexImpl()
 {
-	pthread_mutex_init(&m_handle, NULL);
+	pthread_mutex_init(&m_handle, nullptr);
 }
 
 NzMutexImpl::~NzMutexImpl()
diff --git a/src/Nazara/Core/Posix/ThreadImpl.cpp b/src/Nazara/Core/Posix/ThreadImpl.cpp
index c97abe19c..77099e3c0 100644
--- a/src/Nazara/Core/Posix/ThreadImpl.cpp
+++ b/src/Nazara/Core/Posix/ThreadImpl.cpp
@@ -57,9 +57,9 @@ void NzThreadImpl::Sleep(nzUInt32 time)
 
     // create a mutex and thread condition
     pthread_mutex_t mutex;
-    pthread_mutex_init(&mutex, 0);
+    pthread_mutex_init(&mutex, nullptr);
     pthread_cond_t condition;
-    pthread_cond_init(&condition, 0);
+    pthread_cond_init(&condition, nullptr);
 
     // wait...
     pthread_mutex_lock(&mutex);
diff --git a/src/Nazara/Core/Win32/TaskSchedulerImpl.cpp b/src/Nazara/Core/Win32/TaskSchedulerImpl.cpp
index f0a605d4a..4e1439c2d 100644
--- a/src/Nazara/Core/Win32/TaskSchedulerImpl.cpp
+++ b/src/Nazara/Core/Win32/TaskSchedulerImpl.cpp
@@ -11,7 +11,7 @@
 
 bool NzTaskSchedulerImpl::Initialize(unsigned int workerCount)
 {
-	if (s_workerCount > 0)
+	if (IsInitialized())
 		return true; // Déjà initialisé
 
 	#if NAZARA_CORE_SAFE